Your interpretation was good, although I cannot agree with everything you said.
In my opinion, the storage should yield about 4 tier-one slots. I understand that the storage would be too cheap regarding its capability, and the fact that you could put it on the top slots of your backpack. Saying this, I suggest it costing either quartz/glass, clay or graphite. This way the storage would cost more, meaning the medium storage would be cheaper per slot (creating a need for them instead of the small one), but be available early enough to really help the player before the medium ones are unlocked.
You said: "It should be able to be placed on any slot where it would collide with an adjacent one, like your regular backpack slots or on a medium storage." I think that it should only be usable on any aux-slot, or maybe even on tier-two or higher slots on all platforms. That's because it would look weird if you had it sticking out of a backpack-slot, but in my opinion it would look very good on the top two slots of your backpack, the slots on the buggy, or even the front of rovers. I do agree on what you said about the possibility of ressorces being in the same space( but on different small storages), so it depends of the rotation of the storage if you're able to store something on it or not. If two storage slots would collide, then one would retract. On any other storage(medium or extra-large) they would stay retracted in order to be easily storable and movable. This way, you can store them while not in use.
Please tell me of your opinion on my "solutions", and if you'd like to change something, just reply to this thread.

I and werd02(His discord name) thought of a way storages that are only a single tier-one slot big could be used. This is what we came up with:
The storage would be as big as a small generator when not in use, and extend like a piston once you place it on any aux-slot. It has four tier-one slots, in the formation of a medium storage thats sawed in half(two on the front and two on the back side). It would also have a small platform like a generator when you put it on the ground, thus extending it. We also thought about how we can prohibit players to stack extended storages onto another: if you put one of these onto an extended storage, it won't extend, and you could carry all four items/storages, without creating infinite storage-structures. We currently aren't sure if it would create a cable socket when deployed on the floor, but it might be better for power management and storms. If you know how to improve this idea, feel free to reply to this message!

Maybe the atmosphere could be made out of different stacked gases with different densitys. Then you'd had to choose with wich one of the gases available to you you'd fill your ballon so it gets up to a certain height, but not meaningfull higher.

Many people mentioned the problem that you dont even need to build a shuttle and visit other planets. The tradeplatform was one of the reasons. I suggest that it would need certain augments to be functional the way it is now. Let's say without augments it could only convert scrap to resources.There is one augment-type per planet, and you could only find the research/resource needed to craft it on said planet. E.g. if you attached the terran-augment, the tradeplatform would be capable of trading the resources found on terran. But that means the resources also need to be more planet-specific.